Ask HN: Collaborative apps for young kids in lockdown?

I'm sure many other parents are in this situation - we have an only child (5) who is getting a little sick of only hanging out with his parents and is starting to miss his school friends.

We've had few video chats with his friends, but it isn't really enough to keep him engaged, he likes doing stuff with his friends.

Does anyone have recommendations for games/apps out there where two young kids can work together? It would be great if they could see and talk to one another at the same time.